The present invention is related to a curtain, and more particularly to a roller curtain which can be wound up or unwound down. The roller curtain has a back rolling structure which provides back rolling force for ascending the curtain.
A conventional roller curtain has a reel and a curtain wound on the reel. When rotating the reel, the curtain is released down. When rotating the reel in a reverse direction, the curtain is recovered.
When pulling a bead chain or a pull cord of the roller curtain to drivingly rotate the roller curtain and unwind the curtain, the curtain will fall due to gravity. Therefore, it is easier to release the curtain. Reversely, when winding the curtain, it is necessary to over the gravity so that it is strength-costing to pull the bead chain. In order to solve this problem in operation, a resilient restoring mechanism is installed in the rail of the curtain. The restoring mechanism has a torque spring in which a resilient energy is reserved when releasing the curtain. When winding the curtain, the resilient energy helps in turning back the reel so as to save strength.
It is a primary object of the present invention to provide a roller curtain which is other than torque spring and able to provide back rolling force for ascending the curtain.
The present invention can be best understood through the following description and accompanying drawings wherein: